The present invention relates in general to actuator devices, and more particularly, to a door lock actuator useful, for example, in connection with automotive fuel doors.
In an effort to inhibit unauthorized access to a vehicle""s fuel tank, automobile manufacturers have evaluated various fuel filler door latch systems. Conventionally, fuel filler door latch systems have included the use of a striker fixed to the filler door and a latch member (xe2x80x9chookxe2x80x9d) mounted to the vehicle body. The latch member engages the striker to lock the fuel filler door in a xe2x80x9clatchedxe2x80x9d position. To release the fuel filler door, the latch member is moved to an xe2x80x9cunlatchedxe2x80x9d position to disengage the striker. The fuel filler door is spring loaded to open partially when the latch member moves to the xe2x80x9cunlatchedxe2x80x9d position for allowing the operator to pivot the door to a full open position.
One method of locking the fuel filler door includes the use of a key lock mechanism. However, as a convenience option, vehicle manufacturers are installing remotely actuated fuel filler door latch release systems. Such remotely actuated systems permit an occupant within the passenger compartment of the vehicle to release the fuel filler door prior to exiting the vehicle. Typically, remotely actuated latching systems include the use of linear actuation cables or linkages for manually releasing the filler door. In general, a vehicle occupant pulls a release handle within the passenger compartment to move the latch member out of engagement with the striker. As an alternative, many vehicles are now being equipped with electrically actuated release systems. Electrically actuated systems include a solenoid device mounted remote from the fuel filler area and a linkage coupled between a movable solenoid armature and the latch member. Energization of the solenoid moves the armature and, consequently, the latch member to disengage the striker.
Because the fuel filler door is a cosmetic xe2x80x9cfit and finishxe2x80x9d component of an automobile, it must be precisely aligned during assembly. It is common for conventional fuel filler latching mechanisms to require adjustment of the alignment between the latch member and the striker following vehicle assembly to assure the release system will function properly.
A disadvantage associated with known solenoid operated fuel filler latching mechanisms is the excessive armature travel required to assure adequate system reliability. Conventional solenoid actuated release systems must generate a large armature travel to account for the dimensional variations associated with the components making up a fuel filler door assembly and the latch mechanism. As is known in solenoid design, it is an inherent characteristic that the magnetic attractive force produced by a solenoid device decreases as its armature travel increases. Therefore, to assure release of the striker it has been necessary to provide an extremely large and expensive solenoid to generate a sufficient force output with a sufficiently large travel. Consequently, solenoid actuated fuel filler door latch systems have, until recently, been extremely expensive due to large solenoid requirements to account for dimensional and alignment variations.
Accordingly, there is a need in the art for a fuel filler door actuator that efficiently and reliably establishes the lock state of a fuel filler door while overcoming the deficiencies of conventional latch mechanisms.
According to one aspect of the invention, there is provided a fuel filler door actuator including: a motor; a gear train coupled to the motor and to a latch arm for moving the latch arm between locked and unlocked conditions upon energization of the motor in first and second directions, respectively; and a locking cam coupled to the gear train for resisting movement of the latch arm from the unlocked condition to the locked condition. A manual override cable may be provided for manually moving the latch arm from the locked condition to an unlocked condition. An actuator consistent with the invention may also include a pushxe2x80x94push mechanism for allowing facile opening of a fuel filler door, and may include a quick connect/disconnect feature for allowing facile assembly of the actuator to a fuel filler door housing.